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1.
FASEB J ; 38(11): e23693, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38809685

RESUMO

N6-methylated adenosine (m6A) is a crucial RNA modification in eukaryotes, particularly in cancer. However, its role in cervical cancer (CC) is unclear. We aimed to elucidate the part of m6A in CC by analyzing methyltransferase-like 3 (METTL3) expression, identifying downstream targets, and exploring the underlying mechanism. We assessed METTL3 expression in CC using western blotting, quantitative polymerase chain reaction (qPCR), and immunohistochemistry. In vitro and in vivo experiments examined METTL3's role in CC. We employed RNA sequencing, methylated RNA immunoprecipitation sequencing, qPCR, and RNA immunoprecipitation qPCR to explore METTL3's mechanism in CC. METTL3 expression was upregulated in CC, promoting cell proliferation and metastasis. METTL3 knockdown inhibited human cervical cancer by inactivating AKT/mTOR signaling pathway. METTL3-mediated m6A modification was observed in CC cells, targeting phosphodiesterase 3A (PDE3A). METTL3 catalyzed m6A modification on PDE3A mRNA through YTH domain family protein 3 (YTHDF3). Our study indicated the mechanism of m6A modification in CC and suggested the METTL3/YTHDF3/PDE3A axis as a potential clinical target for CC treatment.


Assuntos
Adenosina , Proliferação de Células , Metiltransferases , Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Camundongos , Adenosina/análogos & derivados , Adenosina/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Metiltransferases/metabolismo , Metiltransferases/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Metilação de RNA/genética
2.
Biomacromolecules ; 25(3): 1527-1540, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38307005

RESUMO

Ionic liquids (ILs) showed a promising application prospect in the field of biomedicine due to their unique recyclability, modifiability, and structure adjustability. In this study, nanoporous microsphere of silk protein and blending with poly(d,l-lactic acid) as model drug delivery was fabricated, respectively, through an IL-induced self-assembly method. Their morphology, structure, and thermal properties were comparably investigated through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry, X-ray diffraction, and thermogravimetric analyses, and the interaction mechanisms were also discussed to elucidate the effect of structure on drug delivery kinetics. The pure protein exhibited a bigger nanopore size in the microsphere compared to the composite one, facilitating more effective drug loading up to 88.7%. However, drug release was over 53.5% for the composite during initial 4 h, while pure protein was only about half of the composite. Both of them exhibited sustained slow release after 24 h and anticancer efficacy. Furthermore, the favorable compatibility between drug and microsphere vehicle was found and experienced improved thermal stability upon encapsulation, which could protect the drug molecules in high temperature at 200 °C. When the protein and its composite self-assembled to microspheres in ILs due to electrostatic and hydrophobic interaction, the drug could be infiltrated into the nanoporous matrix through biophysical action, and the protein structure displayed reversible transition during delivery. The sustained slow release from pure SF was attributed to the high ß-sheet block action and strong drug-protein interactions, whose strength could be tuned through blending poly(d,l-lactic acid) with protein. These findings indicated that the SF-based nanoporous microspheres formed from IL self-assembled system are an ideal and potential drug delivery vehicle which can be incorporated into various biomaterials in the future.


Assuntos
Líquidos Iônicos , Nanoporos , Seda/química , Microesferas , Sistemas de Liberação de Medicamentos , Ácido Láctico/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
3.
J Comput Chem ; 44(29): 2294-2301, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37466308

RESUMO

Species generally exhibit one-state aromaticity either in the lowest singlet state (S0 ) or the lowest triplet state (T1 ) according to the Hückel's and Baird's rules. Hence, it is rare for species exhibit two-state aromaticity in both the S0 and T1 states (termed as adaptive aromaticity), let alone adaptive σ aromaticity. Here, we report adaptive σ aromaticity in unsaturated rhenacyclopropene rings via density functional theory (DFT) calculations. Various aromaticity indices including NICS, ACID, EDDB together with isodesmic reactions support the adaptive σ aromaticity in these rhenacyclopropene rings. As the T1 state of these species is formed by the ππ* excitation, the σ-aromaticity of these three-membered rings in the S0 state could hold in the T1 state. In addition, the aromaticity effect of the fused rings is also examined. Our findings expand the family of adaptive σ aromaticity, enriching the metallaaromatic chemistry.

4.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955840

RESUMO

Ionic liquids (ILs) show a bright application prospect in the field of biomedicine and energy materials due to their unique recyclable, modifiability, structure of cation and anion adjustability, as well as excellent physical and chemical properties. Dissolving silk fibroin (SF), from different species silkworm cocoons, with ILs is considered an effective new way to obtain biomaterials with highly enhanced/tailored properties, which can significantly overcome the shortcomings of traditional preparation methods, such as the cumbersome, time-consuming and the organic toxicity caused by manufacture. In this paper, the basic structure and properties of SF and the preparation methods of traditional regenerated SF solution are first introduced. Then, the dissolving mechanism and main influencing factors of ILs for SF are expounded, and the fabrication methods, material structure and properties of SF blending with natural biological protein, inorganic matter, synthetic polymer, carbon nanotube and graphene oxide in the ILs solution system are introduced. Additionally, our work summarizes the biomedicine and tissue engineering applications of silk-based materials dissolved through various ILs. Finally, according to the deficiency of ILs for dissolving SF at a high melting point and expensive cost, their further study and future development trend are prospected.


Assuntos
Fibroínas , Líquidos Iônicos , Materiais Biocompatíveis/química , Fibroínas/química , Líquidos Iônicos/química , Seda/química , Engenharia Tecidual/métodos
5.
J Org Chem ; 85(23): 15197-15212, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33161704

RESUMO

Four binuclear tridentate copper(I) complexes were synthesized based on the trans effect of the hybrid ligands. The catalytic performance and behavior of the prepared copper(I) complexes were evaluated in the carboxylative cyclization of propargylic amines with CO2. The combined use of copper(I) complexes and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) provided a catalytic system for the synthesis of a wide range of oxazolidinones from various propargylic amines and CO2 under mild reaction conditions (room temperature-40 °C and 1 bar CO2). The key factor for the success of the protocol is the use of copper complexes possessing the quality of hemilabile properties between N-heterocyclic carbenes and nitrogen donors. NMR measurements, density functional theory (DFT) calculations, and previous reports for the coordination behavior of the nickel complexes support the existence of the trans effect between N-heterocyclic carbenes and nitrogen donors.

6.
Org Biomol Chem ; 18(35): 6781-6800, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32857085

RESUMO

Different from the traditional role of a Brønsted base, amines/imines have been widely employed during the past few decades as a Lewis base to activate electrophilic allene, olefin, and carbonyl compounds. Understanding the detailed mechanisms and the origin of chemo- and stereo-selectivities for these types of reactions should be very important and highly desirable. In this minireview, the recent advances and methods for analysis of the origin of the selectivities of novel Lewis base amine/imine-mediated reactions are systematically summarized and reviewed from a theoretical viewpoint. This information provides valuable insights for understanding the general action modes of Lewis base amine/imine catalysts and rational design of more efficient organocatalytic reactions with high stereoselectivity and special chemoselectivity.

7.
Int J Mol Sci ; 21(11)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512793

RESUMO

Electrospinning has gained constant enthusiasm and wide interest as a novel sustainable material processing technique due to its ease of operation and wide adaptability for fabricating eco-friendly fibers on a nanoscale. In addition, the device working parameters, spinning solution properties, and the environmental factors can have a significant effect on the fibers' morphology during electrospinning. This review summarizes the newly developed principles and influence factors for electrospinning technology in the past five years, including these factors' interactions with the electrospinning mechanism as well as its most recent applications of electrospun natural or sustainable composite materials in biology, environmental protection, energy, and food packaging materials.


Assuntos
Materiais Biocompatíveis/química , Biotecnologia , Fenômenos Químicos , Embalagem de Alimentos , Biotecnologia/métodos , Eletroquímica/métodos
8.
Mol Cancer ; 18(1): 181, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823788

RESUMO

BACKGROUND: Brain metastasis (BM) is one of the principal causes of mortality for lung cancer patients. While the molecular events that govern BM of lung cancer remain frustrating cloudy. METHODS: The miRNA expression profiles are checked in the paired human BM and primary lung cancer tissues. The effect of miR-143-3p on BM of lung cancer cells and its related mechanisms are investigated. RESULTS: miR-143-3p is upregulated in the paired BM tissues as compared with that in primary cancer tissues. It can increase the invasion capability of in vitro blood brain barrier (BBB) model and angiogenesis of lung cancer by targeting the three binding sites of 3'UTR of vasohibin-1 (VASH1) to inhibit its expression. Mechanistically, VASH1 can increase the ubiquitylation of VEGFA to trigger the proteasome mediated degradation, further, it can endow the tubulin depolymerization through detyrosination to increase the cell motility. m6A methyltransferase Mettl3 can increase the splicing of precursor miR-143-3p to facilitate its biogenesis. Moreover, miR-143-3p/VASH1 axis acts as adverse prognosis factors for in vivo progression and overall survival (OS) rate of lung cancer. CONCLUSIONS: Our work implicates a causal role of the miR-143-3p/VASH1 axis in BM of lung cancers and suggests their critical roles in lung cancer pathogenesis.


Assuntos
Adenosina/análogos & derivados , Neoplasias Encefálicas/secundário , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Modelos Biológicos , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Interferência de RNA , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cancer ; 125(20): 3535-3544, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31287555

RESUMO

BACKGROUND: Patients with brain metastases (BMs) have a poor prognosis and limited therapeutic options. Lung cancer is the most common primary malignancy giving rise to BMs; thus, understanding the molecular mechanisms behind increased BM risk is essential for identifying therapeutic targets and developing effective interventions. METHODS: Sixty-one patients who underwent surgical resection of primary non-small cell lung cancer (NSCLC) and BMs were retrospectively studied. Comprehensive genomic profiling of primary NSCLC and matched BMs was performed with next-generation sequencing targeting 416 cancer-relevant genes. RESULTS: Mutations of major drivers, including EGFR, KRAS, TP53, and ALK, were highly concordant between primary NSCLC and matched BMs (>80%), whereas discordance suggested the unique genomic evolution and oncogenic mechanisms of NSCLC BMs. BMs also demonstrated higher levels of copy number variations in comparison with primary NSCLC. Furthermore, the alterations of genes encoding CDK4/CCND1, CDKN2A/2B, and PI3K signaling pathways were enriched in BMs, and this suggested their correlation with increased metastatic risk. Indeed, patients with activated PI3K signaling in their primary NSCLC had significantly shorter BM-free survival (hazard ratio, 8.49; P = .0005). In addition, mutated TP53 or an activated WNT pathway via CTNNB1, APC, and AXIN2 mutations trended toward shorter BM-free intervals but not significantly so. CONCLUSIONS: These findings yield detailed insights into the genomic complexity and heterogeneity of primary NSCLC and matched BMs. This study highlights the significant correlation of PI3K signaling with increased metastatic risk in patients with NSCLC and identifies genomic alterations enriched in NSCLC BMs that could serve as prognostic markers and potential therapeutic targets for treating patients with NSCLC BMs.


Assuntos
Neoplasias Encefálicas/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Neoplasias/genética , Transcriptoma/genética , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Variações do Número de Cópias de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Instabilidade Genômica/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Metástase Neoplásica , Estudos Retrospectivos
11.
J Neurovirol ; 22(5): 607-614, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27021072

RESUMO

Previous neuroimaging studies suggest a negative relationship between the apolipoprotein (ApoE) ε4 allele and brain integrity in human immunodeficiency virus (HIV)-infected (HIV+) individuals, although the presence of this relationship across adulthood remains unclear. The purpose of this study is to clarify the discrepancies using a large, diverse group of HIV+ individuals and multiple imaging modalities sensitive to HIV. The association of ApoE ε4 with structural neuroimaging and magnetic resonance spectroscopy (MRS) was examined in 237 HIV+ individuals in the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) study. Cortical and subcortical gray matter, abnormal and total white matter, ventricles, sulcal cerebrospinal fluid (CSF), and cerebellar gray matter, white matter, and CSF volumes, and MRS concentrations of myo-inositol, creatine, N-acetyl-aspartate, and choline in the frontal white matter (FWM), frontal gray matter (FGM), and basal ganglia were examined. Secondary analyses explored this relationship separately in individuals ≥50 years old (n = 173) and <50 years old (n = 63). No significant differences were observed between ApoE ε4+ (ApoE ε3/ε4 and ApoE ε4/ε4) individuals (n = 69) and ApoE ε4- (ApoE ε2/ε3 and ApoE ε3/ε3) individuals (n = 167). When individuals were further divided by age, no significant genotype group differences were identified in individuals <50 or ≥50 years of age on any neuroimaging outcome. The ApoE ε4 allele did not affect brain integrity in this large, diverse sample of HIV+ individuals. The effects of ApoE ε4 may not be apparent until more advanced ages and may be more prominent when present along with other risk factors for neuronal damage.


Assuntos
Apolipoproteína E4/genética , Córtex Cerebral/diagnóstico por imagem , Genótipo , Infecções por HIV/diagnóstico por imagem , Adulto , Alelos , Antineoplásicos/uso terapêutico , Apolipoproteína E4/sangue , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/metabolismo , Cerebelo/diagnóstico por imagem , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/metabolismo , Estudos de Coortes , Feminino , Expressão Gênica , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fatores de Risco , Substância Branca/diagnóstico por imagem , Substância Branca/metabolismo
12.
J Infect Dis ; 210(10): 1562-72, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24903666

RESUMO

BACKGROUND: Plasmodium falciparum infection induces human immunodeficiency virus (HIV) replication and accelerates a decline in CD4(+) T-cell count. The mechanisms contributing to these interactions have not been fully elucidated. METHODS: We infected peripheral blood mononuclear cells (PBMCs) with HIV type 1 (HIV-1) and then cocultured them with P. falciparum-infected red blood cells (iRBCs) or uninfected RBCs (uRBCs). Levels of HIV-1 p24 antigen and activation-associated cytokines were measured in culture supernatants. T-cell surface activation was assessed by flow cytometry. RESULTS: It has been reported that iRBCs increase HIV replication, compared with uRBCs; that neutralizing tumor necrosis factor α (TNF-α) abrogates this increase; and that hemozoin enhances HIV production. In this study, we confirmed that TNF-α plays an important role in this interaction. We show that iRBCs increased CD4(+) T-cell expression of HLA-DR(+)/CD38(+) (P = .001), that monocyte/macrophage depletion reduced HIV production by 40%-50% (P < .001), and that hemozoin-laden monocytes/macrophages that were preincubated with iRBCs also stimulated HIV production. CONCLUSIONS: iRBCs activate CD4(+) T cells and stimulate HIV replication in a TNF-α-dependent manner following malarial antigen processing by monocytes/macrophages. These results suggest that the persistent elevation of HIV replication during and after acute bouts of P. falciparum malaria may be due, at least in part, to ongoing stimulation of CD4(+) T cells by hemozoin-loaded antigen-presenting cells within lymphoid tissues.


Assuntos
Células Apresentadoras de Antígenos/imunologia , HIV-1/fisiologia , Fagócitos/imunologia , Fagocitose , Plasmodium falciparum/imunologia , Replicação Viral , Técnicas de Cocultura , Meios de Cultura/química , Citocinas/análise , Proteína do Núcleo p24 do HIV/análise , Humanos
13.
Food Chem ; 464(Pt 1): 141677, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39437529

RESUMO

Simplified and effective pretreatment methods combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of four aminoglycoside antibiotic pesticides kasugamycin, validamycin, streptomycin sulfate and zhongshengmycin in high starchy content matrix (rice), high water and high acidic content matrix (citrus) and high water content matrix (melon) were established. Single-factor and central composite design (CCD) experiments were employed to optimize the pretreatment conditions, resulting in the optimal factor combinations and achieving scientifically accurate outcomes. Validation results proved satisfactory, with all four target compounds exhibiting correlation coefficients (r) exceeding 0.99 within the linear range in three matrices. The recoveries were 81.5-102.2 %, and both inter-day and intra-day relative standard deviations (RSDs) were below 10.7 %. The limits of detection (LODs) were 0.1-4.0 µg/kg, with limits of quantitation (LOQs) consistently at 50 µg/kg. Furthermore, the methods were applied to potato, grape, and cucumber matrices to further validate their applicability.

14.
Food Res Int ; 173(Pt 1): 113322, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803633

RESUMO

Sesame is widely used as a nutritional supplement or condiment because of its nutritious properties and palatable flavor. However, the extensive use of pesticides in sesame fields has paradoxically decreased the nutritional vantage. The current study used QuEChERS with a low-temperature freezing method to develop a multi-residue analytical approach to detect target analytes (pesticides) in sesame seed, sesame oil, sesame paste, and sesame meal. The migration ability of target pesticides during oil processing was investigated using HPLC-MS/MS and GC-MS: 35% of pesticides decreased, with processing factors (PFs) lower than 0.98, whereas 65% migrated from the seed to the oil during processing. The migration success of methoxyfenozide was the highest, while clothianidin and pymetrozine demonstrated a significantly lower rate of transfer. The results provide insight into the types of pesticides that should be used in farming practices of sesame to decrease the impact on human health.


Assuntos
Praguicidas , Sesamum , Humanos , Sesamum/química , Praguicidas/análise , Espectrometria de Massas em Tandem , Óleo de Gergelim , Sementes/química
15.
Insects ; 14(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36835714

RESUMO

Methyl jasmonate (MeJA) is a volatile substance derived from jasmonic acid (JA), and it responds to interbiotic and abiotic stresses by participating in interplant communication. Despite its function in interplant communication, the specific role of MeJA in insect defense responses is poorly understood. In this study, we found that carboxylesterase (CarE) activities, glutathione-S-transferase (GSTs) activities, and cytochrome mono-oxygenases (P450s) content increased more after the feeding of diets containing xanthotoxin, while larvae exposed to MeJA fumigation also showed higher enzyme activity in a dose-dependent manner: lower and medium concentrations of MeJA induced higher detoxification enzyme activities than higher concentrations of MeJA. Moreover, MeJA improved the growth of larvae fed on the control diet without toxins and diets with lower concentrations of xanthotoxin (0.05%); however, MeJA could not protect the larvae against higher concentrations of xanthotoxin (0.1%, 0.2%). In summary, we demonstrated that MeJA is effective at inducing S. litura defense response, but the enhanced detoxifying ability could not overcome the strong toxins.

16.
Cancer Med ; 12(24): 22381-22394, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087815

RESUMO

BACKGROUND: Cornichon homolog 4 (CNIH4) belongs to the CNIH family. It functions as an oncogene in many tumors. However, CNIH4's significance in the immune landscape and its predictive potential in cervical cancer (CESC) is unexplored. METHODS: CNIH4 levels and its effect on the survival of patients with CESC were evaluated using data retrieved from The Cancer Genome Atlas (TCGA). The oncogenic effect of CNIH4 in CESC was determined using small interfering RNA-mediated transfected cell lines and tumorigenesis experiments in animal models. RESULTS: Higher expression of CNIH4 was found in advanced tumor and pathological stages, as well as lymph node metastasis. CNIH4 expression correlated positively with the infiltration of macrophages M2 and resting dendritic cells into the affected tissue. Additionally, functional enrichment of RNA-sequencing of CNIH4-knocked down CESC cell lines showed the association of CNIH4 to the PI3K-Akt signaling pathway. Single-sample gene set enrichment analysis highlighted several immune pathways that were elevated in the CESC samples with enhanced levels of CNIH4, including Type-I and Type-II IFN-response pathways. The impact of CNIH4 on drug sensitivity was further assessed using the GDSC database. As CNIH4 is linked to the immune landscape in CESC, this study determined a four-gene risk prediction signature utilizing CNIH4-related immunomodulators. The risk score quantified from the prediction signature was an independent predictive indicator in CESC. Receiver operating characteristic curve analysis verified the good predictive ability of the four-gene signature in TCGA-CESC cohort. Thus, the CNIH4-related model showed potential as an auxiliary TNM staging system tool. CONCLUSION: CNIH4 may be an effective predictive biomarker for patients with cervical cancer, thus providing new ideas and research directions for CESC.


Assuntos
Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Neoplasias do Colo do Útero/genética , Fosfatidilinositol 3-Quinases , Prognóstico , Oncogenes , Adjuvantes Imunológicos , Receptores Citoplasmáticos e Nucleares
17.
Int J Biol Macromol ; 197: 55-67, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34952094

RESUMO

One of the most effective and promising strategies to develop novel biomaterials with unique, tunable structure and physicochemical properties is by creating composite materials that combine synthetic polymers with natural proteins using ionic liquids. In this study, biodegradable poly(d,l-lactic acid) (PDLLA) was blended with silk fibroin (SF) to create biocompatible films using an ionic liquid-based binary solvent system (1-butyl-3-methylimidazolium chloride/N,N-dimethylformamide), which can maintain the molecular weights of the proteins/polymers and encourage intermolecular interactions between the molecules. The effects of varying the ratio of PLA to SF were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), water contact angle testing, and cytotoxicity analysis as well as enzymatic degradation. Results showed that the composite films were homogeneously blended on the macroscopic scale and exhibited typical fully miscible polymer blend characteristics. By increasing the SF content in the composites, the amounts of ß-sheets in the films were significantly increased, allowing for SF to act as a physical crosslinker to maintain the stability of the protein-polymer network. Additionally, SF significantly improved the hydrophilicity and biocompatibility of the material and promoted the self-assembly of micelle structures in the biocomposites. Different topologies in the films also provided beneficial surface morphology for cell adhesion, growth, and proliferation. Overall, this study demonstrated an effective fabrication method for a fine-tuned polymer blends combining synthetic polymer and protein for a wide variety of biomedical and green material applications.


Assuntos
Fibroínas
18.
Plant Signal Behav ; 17(1): 2096790, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35876337

RESUMO

Herbivore-induced defense responses are often specific, whereas plants could induce distinct defense responses corresponding to infestation by different herbivorous insects. Brown plant hopper (BPH) Nilaparvata lugens, a phloem-feeding insect, and rice leaf folder (LF) Cnaphalocrocis medinalis, a chewing insect, are both specialist herbivores on rice. To characterize the distinct resistance primed by prior damage to these two specialist herbivores, we challenged rice plants with two herbivores during vegetative growth of parent plants and assessed plant resistance in subsequent ratoons. Here, we show that LF and BPH induce different suites of defense responses in parent rice plants, LF induced higher level of JA accumulation and OsAOS, OsCOI1 transcripts, while BPH induced higher accumulation of SA and OsPAL1 transcripts. Moreover, an apparent loss of LF resistance was observed in OsAOS, OsCOI1 RNAi lines. Ratoon plants generated from parents receiving prior LF infestation exhibited higher jasmonic acid (JA) levels and elevated levels of transcripts of defense-related genes associated with JA signaling, while ratoon generated from parents receiving prior BPH infestation exhibited higher salicylic acid (SA) levels and elevated levels of transcripts of defense-related genes associated with SA signaling. Moreover, previous LF infestation obviously elevated ratoons resistance to LF, while previous infestation by BPH led to enhanced resistance in ratoons to BPH. Pre-priming of ratoons defense to LF was significantly reduced in OsAOS and OsCOI1 RNAi plant, but silencing OsAOS and OsCOI1 did not attenuate ratoons resistance to BPH. These results suggest that infestation of two specialist herbivores with different feeding styles in parent crop led to distinct defense responses in subsequent rations, and the acquired resistance to LF in ratoons is associated with priming of jasmonic acid-dependent defense responses.


Assuntos
Hemípteros , Mariposas , Oryza , Animais , Regulação da Expressão Gênica de Plantas , Hemípteros/fisiologia , Oryza/genética , Ácido Salicílico
19.
Medicine (Baltimore) ; 101(10): e28875, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35451380

RESUMO

RATIONALE: X-linked chronic granulomatous disease (X-CGD) is an X-linked recessive disorder of the Nicotinamide adenine dinucleotide phosphate oxidase system that can cause primary immunodeficiency. Mutations in the CYBB gene located in Xp21.1 were accounting for X-CGD disease. More than 600 mutations have been identified as the cause of X-CGD in various populations worldwide. PATIENT CONCERNS AND DIAGNOSIS: In this study, the proband suffered from elevated white blood cells (WBC, 23.65 × 109/L), mainly in neutral (16.4 × 109/L). The neutrophil oxidative index of the patient was 2.13, which was extremely low, whereas his mother was 69.0 (Ref >100). Next, next-generation sequencing of the primary immunodeficiency diseases -related gene panel was performed. One novel mutation was identified in the CYBB gene in the CGD case: c.55C>G in exon 2. The mutation was verified by Sanger sequencing. The mother of the patient was heterozygous for the c.55C>G mutation, and the father was normal. These mutations were not present in the 100 unrelated normal controls. INTERVENTIONS AND OUTCOMES: The patient died from severe and uncontrollable pulmonary infection at 3 months of age. LESSONS: The identification of these mutations in this study further expands the spectrum of known CYBB gene mutations and contributes to the genetic counseling and prenatal molecular diagnosis of X-CGD.


Assuntos
Doença Granulomatosa Crônica , China , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/genética , Humanos , Recém-Nascido , Mutação , NADPH Oxidase 2/genética , NADPH Oxidases/genética
20.
Chem Asian J ; 16(16): 2346-2350, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34224204

RESUMO

A computational study was contributed to explore the origin of stereoselectivity of NHC-mediated cyclization reaction between benzoic acid and o-phthalaldehyde for asymmetric construction of phthalidyl ester. The most energetically favorable pathway mainly includes the following steps: (1) nucleophilic attack on carbonyl carbon of o-phthalaldehyde by catalyst NHC, (2) formation of Breslow intermediate, (3) oxidation by DQ, (4) asymmetric formation of dual C-O bonds, and (5) dissociation of catalyst with the product. The C-O bond formation was testified as the stereoselectivity-determining step, the R-configurational pathway is more energetically favorable than the S-configurational one. The non-covalent interaction (NCI) and atom-in-molecule (AIM) analyses were performed to reveal that the O-H ⋅⋅⋅ O and C-H ⋅⋅⋅ O hydrogen-bond interactions are the key factors for controlling the stereoselectivity. The detailed mechanism and origin of stereoselectivity give useful insights for understanding organocatalytic reactions for asymmetric construction of C-O bond.

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